Sentence Examples


  • The head is seen in front resting on the foot and carrying a median non-retractile snout or rostrum, and a pair of cephalic tentacles at the base of each of which is an eye.
  • NEMERTINA, or Nemerteans (Nemertea), a subdivision of worms,' characterized by the ciliation of the skin, the presence of a retractile proboscis, the simple arrangement of the generative apparatus, and in certain cases by a peculiar pelagic larval stage to which the name " pilidium " has been given.
  • In one genus (Polypocephalus) the place of a rostellum is taken by a crown of retractile tentacles.
  • Another form, Rhopalophorus, has two cephalic tentacles that are retractile and covered with hooks.
  • They may be defined as aquatic animals, forming colonies by budding; with ciliated retractile tentacles and a U-shaped alimentary canal.

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